JP2000320590A - Electromagnetic clutch with brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce integrated errors of parts by disposing a brake ring whose inner circumference is spline-engaged with a coil bobbin on an inner side surface of a disk part of a hub which rotates with a pair of collars, and disposing a ring shaped leaf spring fixed to a brake armature on an outer side surface. SOLUTION: A brake ring 60, whose inside circumference is spline-engaged with a coil bobbin 58, is disposed on the inner side surface of a disk part 56b of a hub 56 which rotates with a pair of collars 51a, 51b. The brake ring 60 pinched against a ring shaped leaf spring 62 is released by the action of magnetic flux bypassing a stator 59, a hub 56, and the brake armature 61, when a clutch is turned on. A clutch armature 55 is attracted with the rotor 52 to perform normal clutch function. It is thus possible to prevent generation of clearances due an integrated errors of parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a small electromagnetic clutch, particularly an electromagnetic clutch with a brake used for feeding paper to a copying machine, a printer or the like.

[0002]

2. Description of the Related Art As an example showing the prior art, Japanese Patent Laid-Open Publication No.
No. 145096 has a built-in coil spring to prevent wear powder from the frictional surface of the brake from falling onto the sliding part of the bearing, and a compact electromagnetic clutch with a brake that can be produced at low cost and is suitable for paper feeding. It has been disclosed. In FIG. 3, the left and right sides of the drawing disclosed in the above-mentioned publication are reversed so as to be in the same direction as the drawing of the present invention, and the comparison is further facilitated. The outline will be described with reference to FIG. 3 (A) of a longitudinal side view and FIG. 3 (B) of a plan view which is a view as viewed from an arrow A of FIG. 3 (A). Referring to FIG. 3A, a first portion which is fitted to the outer periphery of the driven shaft 25 from a portion near the right shaft end and extends to a substantially central portion of the shaft, and has a reduced radial thickness in the middle. Is formed.

The thickness of the inner side of the driven collar is reduced from the position where the first collar 22a is located about halfway in the axial direction on the side opposite to the axial direction, and the outer diameter of the first collar 22a is reduced. The second collar 22b is provided in the portion where the second collar 22b is provided. This second
The collar 22b has a leg 22'b having an inner peripheral portion fitted outside and an outer peripheral surface flush with the outer peripheral surface of the first collar 22a. A second leg portion 22c which is bent in the middle in the radially outward direction, and a leg portion 2 which is bent outwardly in parallel with the leg portion 22'b.
2d, and is formed in a double annular shape with a bottom having a substantially J-shaped cross section. The second collar 22b has a rotor function as described later. Near the left end of the second collar 22b in the axial direction, the bearing 39 and the retaining ring 17 restrict the movement in the axial direction and are surrounded by the protruding portion 23b extending in the radial direction and the leg 23a in the axial direction. An annular shell 23 having an L-shaped cross section is arranged. A coil bobbin 35 having a U-shaped cross section is arranged surrounded by a protruding portion 23b extending in the radial direction of the shell 23 and the leg 23a in the axial direction.

A leg 35 a extending in the radial direction substantially at the center of the coil bobbin 35 in the axial direction is provided with the second collar 22.
It faces the annular leg 22c that rises from the inside in the axial direction to the outside in the radial direction. The coil bobbin 35 includes a leg 35b parallel to the leg 22'b, a side plate 35c closely inward of the outer protruding portion 23b of the shell 23, and an axially outer end of the side plate 35c. And a projection 35d that is bent at a right angle inward in the direction. A ring 33 is disposed radially outward of the leg 22d bent inward in the axial direction of the second collar 22b, and a protrusion 35d of the coil bobbin 35 is disposed in axial alignment with the ring 33. The projection 35d abuts on the slit 33a at the outer end of the ring 33 in the axial direction. Leg 35 of coil bobbin 35
The coil 24 is housed in a recess formed by the a, 35b and the side plate 35c.

Referring to FIGS. 3A and 3B, a projecting portion 23b extending radially outward (upward in the figure) of the disk-shaped shell 23 is provided with a side plate extending in the radial direction of the coil bobbin 35. The outermost shell 23 is in close contact with the outer side of 35c in the axial direction. The shell 23 is provided between the second collar 22b and the leg 35b of the coil bobbin.
A second leg 23 having a cross section parallel to the axis of the L-shaped shell 23;
a and the outermost disk-shaped member 23c perpendicular to the leg 23a. A coil spring 34 is housed between the left end of the lining 33 b fixed to the inner surface of the ring 33 and the axial inner peripheral end of the coil bobbin 35. Near the radial outer end of the second leg 22c of the second collar 22b, the leg 35 of the coil bobbin 35
a, a plurality of gaps 22g penetrating in the axial direction are provided in an arc shape, a friction material 22h is disposed on the outside in the axial direction, and the clutch armature 1
Are supported and arranged by the leaf spring 12c.

[0006] The operation of this prior art will be described.
As shown in (A), the coil spring 34 applies a braking force to the second collar 22b via a lining 33b. On the other hand, when the clutch is energized to excite the coil 24, the ring 33 is attracted to the shell 23 which is a magnetic pole body by the magnetic flux Φ to release the brake as shown in FIG. 3 (A) and especially FIG. 4 (B). And the normal clutch function, that is, the clutch armature 1 is the second collar 2
The torque from the gear 12 is sucked by the gear 2b and transmitted to the driven shaft side via the second collar 22b. A slit 33 as one linking part is provided at an axially outer end of the ring 33.
a, and a projection 35d is provided at the position corresponding to the slit 33a of the coil bobbin 35 as the other linking part.

[0007]

As described above, the relative positions of the members when the clutch is OFF, that is, when the coil is not excited, and when the clutch is excited when the clutch is ON,
These are shown in FIGS. 4A and 4B. In each of these drawings, the second leg 2 is viewed from the inner surface of the retaining ring 17 at the left end in the axial direction.
2c, the distance from the outside of the bearing 39 to the inner surface of the disk portion extending in the radial direction of the shell 23, and the coil spring 34 of the lining 33b from the inner surface of the disk portion of the shell 23 in the radial direction. And the distance from the contact surface with the coil spring 34 to the inner surface of the second collar 22b.

[0008] When the clutch is OFF, the force of the coil spring 34 acts to cause the accumulation error of each part to cause the inner surface of the disk portion of the shell 23 to form a ring (brake armature).
Similarly, a gap δ2 is generated between the bearing 39 and the gap δ1 = − (++) between the bearing 39 and the axially inner surface of the second collar 22b. On the other hand, when the clutch is ON, the magnetic flux Φ acts and the contact surface between the second collar 22b and the lining 33b is separated due to an accumulation error of each part to form a gap δ1, and the gap between the retaining ring 17 and the bearing 39 is a gap δ2. Become.

It is desirable to reduce the gap δ1 in order to enhance the response at the time of excitation. However, since the gap δ1 is caused by an integration error of each part related to the distance or the like, the gap δ1 does not become a constant value and is adjusted by a shim or the like. It is necessary and assembly is not easy. Also, due to the action of the coil spring 34, the gap δ2 is
It is necessary to be smaller than 1, and it is also difficult to absorb due to an accumulation error. Therefore, the integration error of parts is reduced,
It is an object of the present invention to provide an electromagnetic clutch with a brake that does not require gap adjustment.

[0010]

According to the present invention, referring to FIGS. 1 (A), 1 (B), 2 (A) and 2 (B), which will be described later, it rotates together with the collars 51a and 51b. A brake ring 60 whose inner periphery is spline-engaged with the coil bobbin 58 is disposed on the inner side surface of the disk portion 56b of the hub 56, and a ring-shaped leaf spring 62 fixed to a brake armature 61 is disposed on the outer side surface. . Accordingly, when the clutch is OFF, the brake ring 60 is fixed to the disc portion 56b of the hub and the brake armature 61 by the force of the ring-shaped leaf spring 62 as shown in FIGS. 1 (A) and 1 (B). It is sandwiched between the magnetic guide ring 63 and gives a braking action to the hub 56 by frictional force. On the other hand, when the clutch is ON, the brake ring 60 releases the interposed brake ring 60 against the force of the ring-shaped leaf spring 62 by the action of the magnetic flux passing through the stator 59, which is a magnetic pole body, the hub 56, and the brake armature 61. On the other hand, the above problem has been solved by performing the normal clutch function by the clutch armature 55 being attracted to the rotor 52.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1A and 2A are longitudinal side views of an electromagnetic clutch with a brake according to the present invention when it is OFF and when it is ON, respectively. FIGS. 1B and 2B are enlarged views of FIG.
The non-magnetic first collar 51a and the second collar 51b fixedly attached to the driven shaft 50 have first and second step portions 51j and 51k, respectively, at intermediate portions in the axial direction. A rotor 52 that extends radially outward and axially inward is mounted between the step portions 51j and 51k. The leg 52a of the rotor 52 is disposed on the side surface of the step 51j of the first collar 51a, and the second collar 51b extends axially outward (leftward) on the opposite side via the leg 52a, The thin portion 51g of the first collar 51a is placed below the thin portion 51h of the second collar 51b. The thickness of the thick portion of the first collar 51a is equal to the total thickness of the thin portion 51g of the first collar 51a and the thin portion 51h of the second collar 51b. become.

The rotor 52 extends radially outwardly in close contact with the stepped portion 51j, bends inward in the axial direction at this outer end as 52b, and extends on the radially inner peripheral surface 52c of the 52b. The outer peripheral surface of the stator 59 extending in the axial direction is positioned with a gap therebetween. Step 5 of the first collar 51a
1j, a second collar 51b is arranged on the axial side surface of the rotor 52, and the axial section of the first collar 51a and the step portion 51k of the second collar 51b are brought into contact engagement with each other. The two-surface engaging portion is flush. First color 51
A boss 53 having a U-shaped or h-shaped cross section is rotatably mounted on the outer periphery in the radial direction of a, and a gear 54 is further mounted on the outer periphery in the radial direction.
And the gear 54 are fixed with bolts or the like.

In this example, claws 53b at three equal positions are provided on the disk portion 53a of the boss 53 extending in the radial direction and the axial direction so as to protrude inward in the axial direction.
Engages with a groove 55a provided in a disk-shaped clutch armature 55 on the opposite side to the disk portion 53a so as to be slidable in the axial direction. A hub 56 having a radially outwardly extending disk portion 56b is rotatably positioned near an axially outer end of an axially extending leg of the second collar 51b,
As a result, an annular space having an L-shaped cross section is formed. A stator 59 extends radially outward of the disk portion 56b of the hub in parallel with the axis, and the L-shaped cross-section legs 58a, 58 of the stator 59 and the coil bobbin 58 are provided.
d and a gap between the stator 59 and the coil 57.
Is wound.

The above-mentioned coil bobbin 58 is fixed to the fixed arm 5.
A ring-shaped spline portion 58b protrudes in the axial direction at the center of the leg 58d of the coil bobbin 58 by a bolt or the like fixed to a fixed body (not shown) by 8c. A brake ring 60 having an inner periphery that is spline-engaged with the spline portion 58b is positioned so as to face the disk portion 56b of the hub. On the opposite side of the disk portion 56b of the hub from the brake ring 60 in the axial direction, A ring-shaped leaf spring 62 fixed to an annular brake armature 61 having an L-shaped cross section is located. A non-magnetic guide ring 6 having a non-magnetic L-shaped cross section is provided on the radially inner periphery of the brake armature 61.
3 are fitted, ribs 63a are provided at a plurality of locations on the inner periphery of the horizontal portion of the non-magnetic guide ring 63, and the disc portion 5 of the hub is provided.
The brake armature 61 slides in the axial direction by engaging with the groove on the outer periphery of 6b, and 64 is the outermost retaining ring in the axial direction.

Next, the operation of the device of the present invention will be described. When the clutch is in the OFF state when the coil 57 is in the non-excited state,
As shown in FIGS. 1A and 1B, the brake armature 61 is pushed leftward in the figure by the leaf spring 62, and the brake ring 60 is connected to the disc portion 56b of the hub and the nonmagnetic guide ring 63. The brake ring 60 and the disk portion 56b of the hub are fixed to each other by frictional force. The brake ring 60 is connected to the spline portion 58 of the coil bobbin 58.
b, the brake shaft acts on the driven shaft 50 via the hub 56, the rotor 52, the thin portion 51g of the first collar 51a, and the thin portion 51h of the second collar 51b. In this case, the clutch armature 55 is separated from the rotor 52 in the axial direction by inertia, or spins in slight contact and does not hinder the braking operation.

Next, when the clutch is turned on so that the coil 17 is excited, as shown in FIGS. 2A and 2B, a magnetic flux Φ is generated by the coil 57 and the stator 59 and the hub 56 are magnetically poled. The brake armature 61 moves toward the hub disc portion 56b against the force of the leaf spring 62, and the brake ring 60 sandwiched between the hub disc portion 56b and the non-magnetic guide ring 63 Once released, the braking action disappears. On the other hand, the clutch armature 55 is attracted to the side surface of the rotor 52, and the rotation of the gear 54 is performed by rotating the boss disk portion 53a, the claw 53b, the groove 55a, the clutch armature 55, the rotor 52, the first and second collars 51.
The power is transmitted to the driven shaft 50 via the a and 51b to perform a normal clutch function.

[0017]

According to the present invention, as a basic structure, the coil bobbin 58 has an inner periphery formed on the inner side surface of the disk portion 56b of the hub 56 which rotates together with the collars 51a and 51b. Brake ring 6 with spline engagement
0, a ring-shaped leaf spring 62 fixed to a brake armature 61 is provided on the outer side surface.
Since there is no gap due to an accumulation error as in the prior art, shim adjustment is not required, and there is an excellent effect that assembly is extremely easy and assembly cost is greatly reduced. Also,
With the configuration as described in claim 2, the clutch function is accurately performed. Further, when configured as described in claim 3, the product to which the present invention is applied can be made compact.

[Brief description of the drawings]

FIG. 1 (A) is a longitudinal sectional side view of an electromagnetic clutch with a brake according to the present invention when it is OFF, and FIG. 1 (B) is an enlarged view of a brake part of FIG. 1 (A).

FIG. 2A is a longitudinal sectional side view when an electromagnetic clutch with a brake according to the present invention is ON, and FIG. 2B is an enlarged view of a brake portion of FIG.

FIG. 3A is a longitudinal sectional side view of a conventional electromagnetic clutch with a brake, and FIG. 3B is a view taken in the direction of arrow A in FIG. 3A.

4A and 4B are diagrams showing the relative positions of the components of the electromagnetic clutch with brake shown in FIG. 3, wherein FIG. 4A shows the clutch OFF, and FIG. 4B shows the clutch ON.

[Explanation of symbols]

 50: driven shaft 51: collar 51a: first collar 51b: second collar 52: rotor 53: boss 53b: claw 54: gear 55: clutch armature 55a: groove 56: hub 56b: disk portion of the hub 57: Coil 58: Coil bobbin 58b: Spline portion 58c: Fixed arm 59: Stator 60: Brake ring 61: Brake armature 62: Ring-shaped leaf spring 63: Non-magnetic guide ring 64: Retaining ring

Claims (3)

[Claims] 1. A first collar (51a) extending to a substantially central portion of one shaft end portion of a driven shaft (50) and having a reduced thickness in the middle, and the other collar of the driven shaft (50). A second collar (51b) extending to a substantially central portion of the end portion and having a reduced thickness in the middle, wherein the two reduced thickness portions are overlapped on the outer periphery of the driven shaft (50). A collar (51) fixed integrally, the first collar (51a) and the second collar (51b)
A brake ring (60) having an inner periphery spline-engaged with the coil bobbin (58) on the inner side surface of the disc portion (56b) of the hub which is interposed between the hub and the rotor (52) and rotates together with the rotor (52).
And a brake armature (6) on the opposite side of the disk portion.
1) has a ring-shaped leaf spring (62) fixed thereto, and when the clutch is OFF, the elasticity of the leaf spring (62) allows the brake ring (60) to rotate the disc portion (56b) of the hub. And a non-magnetic guide ring (63) fixed to the brake armature (61), and exerts a braking action on the disc portion (56b) of the hub by frictional force. The stator (5
9), the brake armature (61), the hub (5)
6), the rotor (52) and the clutch armature (5
5) releases the brake ring (60) which is sandwiched against the elasticity of the leaf spring (62) by the action of the magnetic flux passing through the clutch armature (55). The gear (54) fixed to the boss (53) is rotated by the rotation of the gear (54) fixed to the boss (53).
The boss (53), the clutch armature (55),
A rotor (52) and the first and second collars (51);
An electromagnetic clutch with a brake, which is transmitted to a driven shaft (50) through (a) and (51b). 2. A plurality of claws (53b) provided at equal angle positions on the outer peripheral edge of the disk portion of the boss (53), and the same number of grooves at corresponding positions for engaging with the claws. (55a)
The electromagnetic clutch with a brake according to claim 1, wherein the clutch armature (55) having the following is disposed so as to be slidable in the axial direction. 3. A gear (5) having a locking member at one end in the axial direction.
4) While restraining the outward movement in the axial direction, the driven shaft (50) extends to near the center of the shaft end portion to reduce the thickness in the radial direction to form the first step (51j). Driven shaft (5
0) and a first collar (51a) fixed to the first step (51a) of the collar (51a). The first collar (51a) extends radially outward in contact with the first step (51j), and is bent axially inward at the outer end. Rotor (52), an axially outer end of the rotor (52) and the gear (54).
A boss (53) that is arranged between the inner end of the boss (53) and forms a predetermined gap between the claw portion at the tip and the axial end surface of the rotor (52); A clutch armature (55) that is housed in a space between the circumference and the claw portion and is attracted to the rotor when the clutch is ON, extends to the shaft end along the first collar (51a), The thickness of the first collar (51a) is reduced at the portion where the radial thickness is reduced, and the second collar (51a) is fixed to the driven shaft (50) by forming a second step (51k). 51
b), and a disk portion (56b) that is in contact with the outer periphery of the second collar (51b) and extends radially outward near the outer end, and has a locking member (64) at the shaft end to move in the axial direction. A hub (56) whose movement is restricted, extending along the radial outer periphery of the hub (56), extending radially outward from the axially inner side from the disk portion (56b), and having an outer end fixed arm A non-magnetic guide ring (58c), which extends in the axial direction in contact with the outer end surface of the disk portion (56b) of the hub (56), and which is further bent inward in the radial direction; 63), a brake ring (60) inserted between the non-magnetic guide ring (63) and the disk portion (56b) of the hub (56), and a non-magnetic guide ring (63). Located radially outward, its outer end bends radially inward A brake armature (61), the leaf spring (62) disposed between the brake armature (61) and the disk portion (56b) of the hub, and a radial direction of an outer periphery of the rotor (52). An annular coil (5) extending toward the coil bobbin (58) in contact with an inner end thereof and housed in a gap between the coil bobbin (58) and the coil bobbin (58).
7) and a brake-equipped electromagnetic clutch including a stator (59).